TEHRAN — Iran has designated Britain's Royal Navy and Royal Air Force as “terrorist organisations” and classified the UK's foreign intelligence service, MI6, as a “hostile group”, the Iranian Foreign Ministry said in a statement on Sunday, 1 November. The measures took effect when the statement was published, the semi-official Tasnim news agency reported.

Source: Tasnim via Azernews, Nov 1

According to the statement, the decision rests on a resolution of Iran's Supreme National Security Council. MI6 is placed under Note 2 of Article 1 of Iran's law on tougher penalties for espionage and cooperation with Israel and “hostile countries”, while the Royal Navy and the RAF are brought under Iran's law on reciprocal action against the United States' designation of the Islamic Revolutionary Guard Corps (IRGC), and are “accordingly recognised as terrorist organisations”, Tasnim reported. China's Xinhua news agency carried the same points.

The reasons Tehran gave

The Foreign Ministry called British policy towards Iran “hostile and unlawful” and said the steps respond to UK actions over the past year — including what Tehran described as Britain's involvement in the US-Israeli war against Iran through the provision of military bases, facilities and logistical support, and London's decision of 13 July 2026 to bring the IRGC under its State Threats Act. Those are Iran's characterisations. The ministry said the measures were consistent with international law and the principle of reciprocity, and that London would bear responsibility for the consequences, Iran's Press TV reported.

Source: Press TV, Nov 1

What Britain did in July

On 13 July 2026 the UK government announced that the IRGC, the Islamic Movement of Companions of the Right (IMCR) and Russia's GRU Volunteer Corps would be the first bodies designated under the new National Security (State Threats) Act 2026. London said supporting or assisting a designated group could bring up to 14 years in prison, and that it had already sanctioned the IRGC in its entirety along with more than 550 Iranian-linked individuals and entities.

Source: UK government release, 13 July 2026, via Defense and Tech

13 July 2026Date Britain designated the IRGC under its State Threats Act
14 yearsMaximum UK prison term for supporting a body designated under that Act, per the UK government
550+Iranian-linked individuals and entities London said it had already sanctioned

What is not yet known

The ministry did not spell out any operational consequences of Sunday's designations for British ships or aircraft, and no UK government response had been published at the time of reporting. The step is, for now, a legal and political one — but it lands while British forces remain active in and around the Gulf, the sea lane on which lakhs of Indian and Punjabi workers in the Gulf states depend for flights, trade and remittances. Tehran has used the same legal tool before: in April 2019, after Washington designated the IRGC a foreign terrorist organisation, Iran declared US Central Command and US forces in the Middle East terrorist entities, Reuters reported at the time.

What is solid

  • Iran's Foreign Ministry published the designations on Sunday and said they took effect immediately, as reported by Tasnim, Press TV and Xinhua
  • Britain designated the IRGC under its State Threats Act on 13 July 2026

What is only claimed

  • Iran's claim that Britain took part in the war against it through bases and logistical support — Tehran's characterisation, not independently established in Sunday's reporting
  • What the designations will mean in practice for British forces — the ministry did not say, and London had not responded at the time of reporting